Are the helmets actually a different shade of green? Or is that just due to the lighting?

Different shade of green on the helmet and around the neck. Chest and crotch plates are the same (dark) as with an area that is painted on the collarbone to the backside. Also, both the capes are a different color, the BH version is painted a darker green than the helmet and the ESB version is more like a dark olive green.